Abstract
Growing homogeneous-phase YIG grains on Si substrates through a low-cost sol-gel route is crucial to the integration of patterned YIG on a Si-based photonic platform. Here, the fabrications of both YIG powders and films are compared for studying their difference in phase transition. A buffered layer of YIP is found necessary for the complete conversion of Y2Fe4O9 phase to YIG phase on Si substrates. Through the optimization of experimental factors, homogeneous-phase YIG grains with micron-scale size and rectangle profile are fabricated on the Si substrate. The narrow and strong Micro-Raman peaks of the as-grown grain reveal the crystal lattice with high perfection while slight shifts of some Raman peaks indicate the residual stress induced by repeated annealing. The magneto-optical property of the YIG grain, characterized on a micron scale by using a home-made system, is found comparable to that of the commercially epitaxial YIG film on a GGG substrate.